NOTE: when you use an email reply to post to this forum, you will want to delete all content that is not related to the actual question. I edited the post to remove all non-essential information, for clarity. If I accidentally removed anything that is relevant, please do let me know. Thank you!

With respect to your second question, there is a lot of decoupling capacitance across the VDD and GND pins, so I would wonder how accurately you can measure this with a digital multimeter. Is that how you are measuring this resistance? Measuring the power supply current might be just as useful.

QUESTION: I would like to ask you

about the impedance between VDD pin and GND pin of ADIS16375 is how much? I

measure it to be about 326 ohm. once again thank you very much!

ALSO: In the future, can you start a separate discussion when you have a separate question? I am sorry if this seems inconvenient, but we have found that this supports the best clarity, which equips us to provide the best possible service. Thank you!